1 The Science Of Psychology Chpt 1

The Science of Psychology Chapter 1 Myers 7th ed. Summary

The limits of intuition and common sense  What

makes something a science?  Intuition and common sense are often wrong.  Hindsight Bias –

People often think something was obviously going to happen AFTER it happens. After people know an answer they will look for reasons to explain and justify it, even if it’s the wrong answer they will become more convinced it’s the right answer.

The limits of intuition and common sense 

Overconfidence –

–

People tend to think they know more than they do. Even after people are shown to be wrong they often insist they were right or partially right

The Scientific Attitude  Being

skeptical but not cynical  Being open but not gullible  Having humility  Valuing the truth over being “right”  Critical thinking – examining the evidence –

“SHOW ME THE EVIDENCE!”

The Scientific Method  Scientific

Theory

An evolving explanation that accurately predicts and organizes observable phenomenon. A scientific theory is only as valuable as its ability to predict outcomes accurately. The ability to predict an action is proven through experimentation – controlled and logical testing that can be repeated by anyone so they can see for themselves the theory works. –

Experimentation  Operational

Definitions – very specifically describes critical concepts in an experiment so that people will be able to replicate it exactly.  Hypothesis – –

A testable prediction An experiment can be very valuable and provide critical information even if it “fails.”

Psychological Research 



Psychologist try to gather information using case studies, surveys, and natural observation. Case studies – – –

Provides in depth information on one subject Good: provides a lot of detailed information Bad: information only definitely applies to that one person and might not be valid for others Skull of Phineas Gage, famous psychological case study

Psychological Research  The – – –

Survey

Gathers information on many subjects but with less detail. Good: Can be used to easily gather a lot of information on a lot of people Bad: Information is not that in depth, results might be tainted by wording effects, or sampling issues

Sampling issues  Survey’s

are a very common powerful tool for research but they can often give misleading information due to sampling issues.  You must find the correct population to draw your sample from.  Within that population you must use random sampling. This avoids the false consensus effect.

Naturalistic Observation  Observing

subjects in their natural setting without trying to control anything. Simply “watching.”  Good – a lot of information can be revealed about how subjects actually act.  Bad – limitations of observer and physically where they are and what they can see.

Correlation  Psychologists

use statistics and correlation to show the strength of a relationship between two things.  However, there are illusionary correlations and cause and effect are still undeterminable.  Correlation does NOT equal causation.

Correlation Coefficient    



The correlation coefficient is just a mathematical way to show how two things relate. A +1.00 coefficient is a perfect positive correlation. So every time thing A happens thing B happens too. A -1.00 is a perfect negative. So every time thing A happens thing B does not. Anything in between expresses a variation of the above. (+.5) means that half the time A occurs B occurs etc. Although correlation does not show effect it does reveal how things relate and is a very useful tool.

Illusory Correlations  When

we believe there is a relationship between two things we are likely to recall and notice instances that confirm our beliefs.  For example, perceiving order in random events… lottery, exact change etc.

Experimentation  In

order to determine cause and effect an experiment must be done.  To find cause and effect experiments attempt to manipulate factors of interest and control all other factors.

Experimental Factors 



Bias – the double blind procedure provides that neither the participants nor the scientists are not aware of who is actually being tested to remove all bias. Placebo effect – a well documented effect in humans, if a patient believes he is getting treatment around 30% of the time he will get better even if he is not. The placebo effect always wears off and is unusable for long term effects.

Experimental and Control groups  Experimental

subjects are randomly selected to be part of the experimental group (the group that will get the experimental treatment) and a Control group (the group that will get a placebo)  This procedure shows the results of the experimental group in contrast to the control group and make for a reliable study of effects.

Independent/Dependant variables  Independent

variable – the thing that will be changed in the experiment between the experimental group and the control group.  Dependant variable – the thing that will be measured in both groups to determine the effect of the independent variable

Basic Stats. 



Stats are used in almost every psychological research paper so they are important to know how to read and interpret. Measures of Central Tendency -Mode: Most frequently occurring number -Median: The number at which half the numbers are above it, and half below. -Mean: The arithmetic average of all numbers

Stats 



Standard Deviation: A computed score that tells how scores vary around the mean score. Statistical Significance: A statistical statement that tells you how likely a result was made by chance (as opposed to actually affected by an independent variable in an experiment.)